Pig production has expanded dramatically in recent years but this has been accompanied by a high cost to the environment.

Special care has to be given to manure management as livestock excreta has a major impact on the environment.

There are plenty of manure management techniques available but they often are not well known.

Also, the farmer or the decision maker frequently has insufficient knowledge of the economic, environmental and public health implications of these techniques.

In order to fill this gap, the LEAD initiative prepared a decision support tool on manure management to facilitate the identification, evaluation and selection of manure management options for confined pig production in rapidly growing economies.

Objectives

This decision support tool was designed to facilitate the identification, evaluation and selection of manure management options for confined pig production.

Selection options would be significantly different if the decision maker’s primary objective was to use the manure as feed or as power generation rather than application on the land.

A decision maker’s objective to sell solid fertiliser would result in a manure management option different from one that would emphasise on the liquid manure system.

This decision support tool is intended for pig producers, farmer associations, extension services and related administration at both the local and national level.

Design

Step 1: Formulate alternative solutions

Manure management system alternatives are developed using the total system approach, which consists of the following five basic functions:

Production

Collection

Storage

Process

Utilisation

Step 2: Inventory manure management options

The entry point for the Decision Support Tool is the collection of manure. The user is then given a choice of manure management options according to the differences in livestock housing structures (concrete floor or partially-slatted floor or slatted floor) and the collection of manure (in house separation or not) and the impact that the collection has on the consistency of the manure (slurry, liquid fraction, solid fraction).

Different options will then be available for the decision maker. For example, the solid fraction of the manure can be composted or treated with the larvae of the black soldier fly or used for earthworm production or stored in heaps (anaerobic storage). For the liquid fraction of manure or slurry, the management options can be grouped as composting, anaerobic digestion, aerobic digestion, separation, storage for sufficient time with cover or with additives, wetlands.

Then the manure can for example be recycled as feed or as fertilizer.

Step 3: Evaluate the manure management options

Alternative manure management options selected by the user will be evaluated to determine if they meet the requirements of the user and if they are socially, environmentally and economically acceptable.

This decision support tool will provide additional information and links for the different options.